Hello,
Does anyone have experience with TCP additive in fuel?
I have been using 100LL in a C-85 for the few hours I have flown this aircraft.
I've read about 3 tanks mogas to one of 100LL (with an auto fuel STC of course), using TCP additive, some use Marvel Mystery Oil.
Forget MMO. Running 100% mogas would be fine (despite the old wives tales espoused by the same idiots who recommend the minty fresh fuel additives, your plane doesn't need lead). If you can't get unleaded, and you run into lead problems, TCP might help. Be **VERY** careful handling this stuff. Nasty (absorbed through the skin and many gloves won't stop it either).
Have used TCP in a C150 and it works well. Definitely worth using along with aggressive leaning.
Have burned mogas for many hundreds of hours with no problem. Small Continentals combustion temps are not high enough to scavenge the lead in 100LL.
Originally Posted by vaflier
It is good to hear the TCP has worked well for you.
The Stromburg carburetor on my engine is unfortunately set full rich with no way to lean. The manual for the engine states that leaning below 5,000 feet is unecessary. Lack of an ability to lean is a subject for another thread.
Had the same engine/carb on my C-120. Flew it at 9,500 ft regularly with no issues. Used 100LL and auto fuel as available with no additives.
Flew my Cherokee 140 for hundreds of hours on auto fuel with zero problems. I have a 0200 in my Champ and burn a mixture of 100LL and 91 octane auto fuel but it runs just fine on auto fuel, too. Just make sure it doesn't have ethanol in it. I had a lot of lead fouling with 100LL in my Cherokee and did try TCP for awhile but auto fuel actually was a better option. Mike
If God had intended man to fly He would have given us more money!
Thanks Ron, Dave, Marty and Mike.
It appears that an auto fuel STC is the way to go. I'm not sure of the available fuel supply without ethanol. It appears two local airfields that had Mogas last year do not have it yet this season. I'll be looking closely at this and will try TCP until I know there are local sources for decent Mogas.
Clarke, I wouldn't worry about 100LL that much. My Luscombe (A-65) ran just fine on it. I had difficulty once finding fuel going from TX to AL, so I put 10 gal of autogas in one tank. (Had 6 or 7 gal of 100LL in the other tank.) I slowly lost RPM. Every 15 minutes, I switched tanks for a minute or two, when it ran normal, switched back to autogas. Took me an hour of that to figure out that the auto gas was causing carb ice. Low vapor preasure dropped venturi temp due to greater evaporation.
Later, I asked the airport's resident expert: "Why are the O-200s having lead problems and I'm not?" He was an A&P/AI, was wearing an OX-5 pin and was older than dirt. He took my engine manual and went to the table on valve timing. he pointed out the big difference between the O-200 and 65, 85, and 90s. He said I would be fine on 100LL.
I was a Nat Guard pilot long ago flying out of AUG and we had a 10,000 gal tank of 115/145 octane. It was the DOD standard for all services. Our people added TCP with several one gal cans per 10,000 gal. Our aircraft had stenciled on the side "Min octane, 91". We all experienced epic plug fouling. I saw plugs pulled with gobs of lead as big as a lima bean. When it happened to me, I was convinced I had thrown a rod. After we moved to Bangor, we got our fuel from another unit and the fouling went away. Could be that we didnt put enough TCP in.
Bob
Years ago, just after buying my Fly Baby (have a C-85), I had an exhaust valve go bad. The cylinder specialist attibuted it to a lack of lead...the engine had only 25 hours when I bought it, and didn't have the lead layer that an older "more experienced" engine would. He recommended I fly at least the first 50 hours with 100LL. IIRC, he replaced my bad valve with one that was more-compatible with lead-free fuel.
This was nearly 20 years ago, not sure how much of this I'm remembering correctly.
In any case, I use both auto fuel and 100LL, and have zilch lead problems. One year was just pure 100LL, when all the car gas had ethanol added to it. Found a source without it, but, again, no lead problems for the year's operation on 100LL.
The upshot is, if you've got an "experienced" engine there's probably been sufficient lead laid down.
Ron Wanttaja
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